The census is conducted on the basis of counting people where they are on census night and provide a "snapshot" of the population. Data on the basis of place of enumeration are available at the Collection District Level and for all Australian Standard Geographic Classification and Census Geographic areas. Most census data is published on the basis of place of enumeration.

Place of Usual Residence

Not all people are at home on census night; they may be in a motel or at a friend's place and not all people enumerated in the census usually live in Australia. Question 7 on the 1996 Census form asks for the address of each person's place of usual residence. This allows statistics to be compiled based on people's place of usual residence. Place of usual residence data are only available for Statistical Local Areas (SLAs), any aggregations of SLAs and Postal Areas.

Estimated Resident Population

Estimated Resident Population (ERP) is the official ABS estimate of the Australian population. The ERP is based on the results of the census and is compiled for each census and updated quarterly between censuses. The ERP is calculated by applying the following adjustments to the usual residence census counts:

include Australian residents who were temporarily absent overseas on census night;

adjust the census counts for undercounting using results of the Post Enumeration Survey; and

backcast the resulting estimates which relate to 6 August 1996 to 30 June 1996 using births, deaths and migration data.

Undercounting

All census counts refer only to people whom census collectors have been able to enumerate on census night. However, a very small number of people and dwellings would have been missed and some might have been counted more than once. The term attached to this is undercounting or under-enumeration.

Geography

Geographic Areas

The geographic areas used for the collection and dissemination of census data are divided into two types: Australian Standard Geographical Classification (ASGC) and Census Geographic Areas. Census data are collected for small areas called Collection Districts. This Collection District base allows the aggregation of data into larger areas, for example, Statistical Local Areas and Electoral Divisions. More information on geographic areas can be found in Statistical Geography (ABS Catalogue Nos 1216.0, 2905.0 and 2909.0).

Australian Standard Geographic Classification

The Australian Standard Geographical Classification (ASGC) is a hierarchically structured classification used by the ABS for the classification of spatial units by geographic areas within Australia.

The ASGC areas used for census purposes are:

Collection District (CD);

Statistical Local Area (SLA);

Local Government Area (LGA);

Statistical Subdivision (SSD);

Statistical Division (SD);

Statistical District (SDIST);

Statistical Region (SR);

Major Statistical Region (MSR);

Urban Centre/Locality (UC/L);

Section of State (SOS); and

State/Territory (S/T).

There is a separate entry in this list of common census terms defining some of these geographic areas.

Census Geographic Areas

Census Geographic areas are generally aggregations of Collection Districts (CDs) that best fit the original area. These CD-derived areas do not necessarily match exactly with the original area. The Population Census is the only ABS collection which provides data for most of these areas:

Commonwealth Electoral Division (CED);

State Electoral Division (SED);

Postal Areas (POC);

Suburb (SSC);

ATSIC Region; and

Indigenous Locations and Indigenous Areas.

Collection District (CD)

The Collection District has been designed for use in the Census of Population and Housing as the smallest unit for collection, processing and output of data and on average contains about 200 dwellings. Collection Districts also serve as the basic building block in the ASGC and are used for the aggregation of statistics to larger ASGC areas and Census Geographic Areas such as Commonwealth and State Electoral Divisions.

Postal Area (previously Collection District Derived Postcodes)

Postal Areas are approximations of Australia Post Postcodes and are created by allocating Collection Districts (CDs) to existing postcodes on a best fit basis. A Postal Area boundary is then created to encompass all of the allocated CDs and the data for the CDs are aggregated to form Postal Area data.

Electoral Divisions (State and Commonwealth)

Electoral Divisions are Census Geographic Areas. They are approximated by aggregating the data for Collection Districts that lie wholly or partly within the Electoral Division. Note: Due to copyright issues, State Electoral Divisions for Western Australia are not available.

Local Government Area (LGA)

The Local Government Area (LGA) is a geographic area under the responsibility of an incorporated local government council. The LGAs in Australia collectively cover only a part of Australia. The major areas not covered by LGAs are the large northern parts of South Australia, almost all of the Northern Territory and all of the Australian Capital Territory.

The number of LGAs and their boundaries can change over time. The LGAs applicable to the 1996 Census output are those which existed at 1 July 1996. Their creation and delimitation is the responsibility of the respective State Governments, and are governed by the provisions of State local government acts.

Statistical Local Area (SLA)

Statistical Local Areas are areas defined in the ASGC which consist of one or more Collection Districts. They can be based on Local Government Areas, or parts thereof, or any unincorporated area. They cover, in aggregate, the whole of Australia without gaps or overlaps.

Statistical Division (SD)

Statistical Divisions are areas defined in the ASGC which consist of one or more Statistical Subdivisions and cover, in aggregate, the whole of Australia without gaps or overlaps. They do not cross State or Territory boundaries and are the largest statistical area building blocks of States and Territories.

SDs are used as large, general purpose regional type geographic areas.

Urban Centre/Locality (UC/L)

An urban centre is a population cluster of 1,000 or more people. A locality is a population cluster of between 200 to 999 people. People living in urban centres are classified as urban for statistical purposes while those in localities are classified as rural. Each urban centre and/or locality (UC/L) is bounded (i.e. a boundary for it is clearly defined) and composed of one or more whole collection district.

UC/Ls are defined for each census and are current for the date of the census. The criteria for bounding UC/Ls are based on the Linge methodology.

Unless otherwise noted, content on this website is licensed under a Creative Commons Attribution 2.5 Australia Licence together with any terms, conditions and exclusions as set out in the website Copyright notice. For permission to do anything beyond the scope of this licence and copyright terms contact us.